/*
www.sourceforge.net/projects/tinyxml
Original code (2.0 and earlier )copyright (c) 2000-2002 Lee Thomason (www.grinninglizard.com)

This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any
damages arising from the use of this software.

Permission is granted to anyone to use this software for any
purpose, including commercial applications, and to alter it and
redistribute it freely, subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must
not claim that you wrote the original software. If you use this
software in a product, an acknowledgment in the product documentation
would be appreciated but is not required.

2. Altered source versions must be plainly marked as such, and
must not be misrepresented as being the original software.

3. This notice may not be removed or altered from any source
distribution.
*/

#pragma once

#ifdef _MSC_VER
#pragma warning( disable : 4530 )
#pragma warning( disable : 4786 )
#pragma warning( disable : 4996 )
#endif

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

// Help out windows:
#if defined( _DEBUG ) && !defined( DEBUG )
#define DEBUG
#endif

#if defined( DEBUG ) && defined( _MSC_VER )
#include <windows.h>
#define TIXML_LOG OutputDebugString
#else
#define TIXML_LOG printf
#endif

#include <string>
#include <iostream>

#define TIXML_STRING    std::string
#define TIXML_ISTREAM    std::istream
#define TIXML_OSTREAM    std::ostream

class TiXmlDocument;

class TiXmlElement;

class TiXmlComment;

class TiXmlUnknown;

class TiXmlAttribute;

class TiXmlText;

class TiXmlDeclaration;

class TiXmlParsingData;

const int TIXML_MAJOR_VERSION = 2;
const int TIXML_MINOR_VERSION = 3;
const int TIXML_PATCH_VERSION = 1;

/*	Internal structure for tracking location of items 
	in the XML file.
*/
struct TiXmlCursor {
    TiXmlCursor() { Clear(); }

    void Clear() { row = col = -1; }

    int row;    // 0 based.
    int col;    // 0 based.
};


// Only used by Attribute::Query functions
enum {
    TIXML_SUCCESS,
    TIXML_NO_ATTRIBUTE,
    TIXML_WRONG_TYPE
};


// Used by the parsing routines.
enum TiXmlEncoding {
    TIXML_ENCODING_UNKNOWN,
    TIXML_ENCODING_UTF8,
    TIXML_ENCODING_LEGACY
};

const TiXmlEncoding TIXML_DEFAULT_ENCODING = TIXML_ENCODING_UNKNOWN;

/** TiXmlBase is a base class for every class in TinyXml.
	It does little except to establish that TinyXml classes
	can be printed and provide some utility functions.

	In XML, the document and elements can contain
	other elements and other types of nodes.

	@verbatim
	A Document can contain:	Element	(container or leaf)
							Comment (leaf)
							Unknown (leaf)
							Declaration( leaf )

	An Element can contain:	Element (container or leaf)
							Text	(leaf)
							Attributes (not on tree)
							Comment (leaf)
							Unknown (leaf)

	A Decleration contains: Attributes (not on tree)
	@endverbatim
*/
class TiXmlBase {
    friend class TiXmlNode;

    friend class TiXmlElement;

    friend class TiXmlDocument;

public:
    TiXmlBase() : userData(0) {}

    virtual ~TiXmlBase() {}

    /**	The world does not agree on whether white space should be kept or
        not. In order to make everyone happy, these global, static functions
        are provided to std::set whether or not TinyXml will condense all white space
        into a single space or not. The default is to condense. Note changing this
        values is not thread safe.
    */
    static void SetCondenseWhiteSpace(bool condense) { condenseWhiteSpace = condense; }

    /// Return the current white space setting.
    static bool IsWhiteSpaceCondensed() { return condenseWhiteSpace; }

    /** Return the position, in the original source file, of this node or attribute.
        The row and column are 1-based. (That is the first row and first column is
        1,1). If the returns values are 0 or less, then the parser does not have
        a row and column value.

        Generally, the row and column value will be std::set when the TiXmlDocument::Load(),
        TiXmlDocument::LoadFile(), or any TiXmlNode::Parse() is called. It will NOT be std::set
        when the DOM was created from operator>>.

        The values reflect the initial load. Once the DOM is modified programmatically
        (by adding or changing nodes and attributes) the new values will NOT update to
        reflect changes in the document.

        There is a minor performance cost to computing the row and column. Computation
        can be disabled if TiXmlDocument::SetTabSize() is called with 0 as the value.

        @sa TiXmlDocument::SetTabSize()
    */
    int Row() const { return location.row + 1; }

    int Column() const { return location.col + 1; }    ///< See Row()

    void SetUserData(void *user) { userData = user; }

    void *GetUserData() { return userData; }

    // Table that returs, for a given lead byte, the total number of bytes
    // in the UTF-8 sequence.
    static const int utf8ByteTable[256];

    virtual const char *Parse(const char *p,
                              TiXmlParsingData *data,
                              TiXmlEncoding encoding /*= TIXML_ENCODING_UNKNOWN */ ) = 0;

protected:

    // See STL_STRING_BUG
    // Utility class to overcome a bug.
    class StringToBuffer {
    public:
        StringToBuffer(const TIXML_STRING &str);

        ~StringToBuffer();

        char *buffer;
    };

    static const char *SkipWhiteSpace(const char *, TiXmlEncoding encoding);

    inline static bool IsWhiteSpace(char c) {
        return (isspace((unsigned char) c) || c == '\n' || c == '\r');
    }

    virtual void StreamOut(TIXML_OSTREAM *) const = 0;

    static bool StreamWhiteSpace(TIXML_ISTREAM *in, TIXML_STRING *tag);

    static bool StreamTo(TIXML_ISTREAM *in, int character, TIXML_STRING *tag);

    /*	Reads an XML name into the std::string provided. Returns
        a pointer just past the last character of the name,
        or 0 if the function has an error.
    */
    static const char *ReadName(const char *p, TIXML_STRING *name, TiXmlEncoding encoding);

    /*	Reads text. Returns a pointer past the given end tag.
        Wickedly complex options, but it keeps the (sensitive) code in one place.
    */
    static const char *ReadText(const char *in,                // where to start
                                TIXML_STRING *text,            // the std::string read
                                bool ignoreWhiteSpace,        // whether to keep the white space
                                const char *endTag,            // what ends this text
                                bool ignoreCase,            // whether to ignore case in the end tag
                                TiXmlEncoding encoding);    // the current encoding

    // If an entity has been found, transform it into a character.
    static const char *GetEntity(const char *in, char *value, int *length, TiXmlEncoding encoding);

    // Get a character, while interpreting entities.
    // The length can be from 0 to 4 bytes.
    inline static const char *GetChar(const char *p, char *_value, int *length, TiXmlEncoding encoding) {
        assert(p);
        if (encoding == TIXML_ENCODING_UTF8) {
            *length = utf8ByteTable[*((unsigned char *) p)];
            assert(*length >= 0 && *length < 5);
        } else {
            *length = 1;
        }

        if (*length == 1) {
            if (*p == '&')
                return GetEntity(p, _value, length, encoding);
            *_value = *p;
            return p + 1;
        } else if (*length) {
            strncpy(_value, p, *length);
            return p + (*length);
        } else {
            // Not valid text.
            return 0;
        }
    }

    // Puts a std::string to a stream, expanding entities as it goes.
    // Note this should not contian the '<', '>', etc, or they will be transformed into entities!
    static void PutString(const TIXML_STRING &str, TIXML_OSTREAM *out);

    static void PutString(const TIXML_STRING &str, TIXML_STRING *out);

    // Return true if the next characters in the stream are any of the endTag sequences.
    // Ignore case only works for english, and should only be relied on when comparing
    // to Engilish words: StringEqual( p, "version", true ) is fine.
    static bool StringEqual(const char *p,
                            const char *endTag,
                            bool ignoreCase,
                            TiXmlEncoding encoding);


    enum {
        TIXML_NO_ERROR = 0,
        TIXML_ERROR,
        TIXML_ERROR_OPENING_FILE,
        TIXML_ERROR_OUT_OF_MEMORY,
        TIXML_ERROR_PARSING_ELEMENT,
        TIXML_ERROR_FAILED_TO_READ_ELEMENT_NAME,
        TIXML_ERROR_READING_ELEMENT_VALUE,
        TIXML_ERROR_READING_ATTRIBUTES,
        TIXML_ERROR_PARSING_EMPTY,
        TIXML_ERROR_READING_END_TAG,
        TIXML_ERROR_PARSING_UNKNOWN,
        TIXML_ERROR_PARSING_COMMENT,
        TIXML_ERROR_PARSING_DECLARATION,
        TIXML_ERROR_DOCUMENT_EMPTY,
        TIXML_ERROR_EMBEDDED_NULL,

        TIXML_ERROR_STRING_COUNT
    };
    static const char *errorString[TIXML_ERROR_STRING_COUNT];

    TiXmlCursor location;

    /// Field containing a generic user pointer
    void *userData;

    // None of these methods are reliable for any language except English.
    // Good for approximation, not great for accuracy.
    static int IsAlpha(unsigned char anyByte, TiXmlEncoding encoding);

    static int IsAlphaNum(unsigned char anyByte, TiXmlEncoding encoding);

    inline static int ToLower(int v, TiXmlEncoding encoding) {
        if (encoding == TIXML_ENCODING_UTF8) {
            if (v < 128) return tolower(v);
            return v;
        } else {
            return tolower(v);
        }
    }

    static void ConvertUTF32ToUTF8(unsigned long input, char *output, int *length);

private:
    TiXmlBase(const TiXmlBase &);                // not implemented.
    void operator=(const TiXmlBase &base);    // not allowed.

    struct Entity {
        const char *str;
        unsigned int strLength;
        char chr;
    };
    enum {
        TINYXML_NUM_ENTITY = 5,
        MAX_ENTITY_LENGTH = 6

    };
    static Entity entity[TINYXML_NUM_ENTITY];
    static bool condenseWhiteSpace;
};


/** The parent class for everything in the Document Object Model.
	(Except for attributes).
	Nodes have siblings, a parent, and children. A node can be
	in a document, or stand on its own. The type of a TiXmlNode
	can be queried, and it can be cast to its more defined type.
*/
class TiXmlNode : public TiXmlBase {
    friend class TiXmlDocument;

    friend class TiXmlElement;

public:
    /** An input stream operator, for every class. Tolerant of newlines and
        formatting, but doesn't expect them.
    */
    friend std::istream &operator>>(std::istream &in, TiXmlNode &base);

    /** An output stream operator, for every class. Note that this outputs
        without any newlines or formatting, as opposed to Print(), which
        includes tabs and new lines.

        The operator<< and operator>> are not completely symmetric. Writing
        a node to a stream is very well defined. You'll get a nice stream
        of output, without any extra whitespace or newlines.

        But reading is not as well defined. (As it always is.) If you create
        a TiXmlElement (for example) and read that from an input stream,
        the text needs to define an element or junk will result. This is
        true of all input streams, but it's worth keeping in mind.

        A TiXmlDocument will read nodes until it reads a root element, and
        all the children of that root element.
    */
    friend std::ostream &operator<<(std::ostream &out, const TiXmlNode &base);

    /// Appends the XML node or attribute to a std::string.
    friend std::string &operator<<(std::string &out, const TiXmlNode &base);


    /** The types of XML nodes supported by TinyXml. (All the
            unsupported types are picked up by UNKNOWN.)
    */
    enum NodeType {
        DOCUMENT,
        ELEMENT,
        COMMENT,
        UNKNOWN,
        TEXT,
        DECLARATION,
        TYPECOUNT
    };

    virtual ~TiXmlNode();

    /** The meaning of 'value' changes for the specific type of
        TiXmlNode.
        @verbatim
        Document:	filename of the xml file
        Element:	name of the element
        Comment:	the comment text
        Unknown:	the tag contents
        Text:		the text std::string
        @endverbatim

        The subclasses will wrap this function.
    */
    const char *Value() const { return value.c_str(); }

    /** Changes the value of the node. Defined as:
        @verbatim
        Document:	filename of the xml file
        Element:	name of the element
        Comment:	the comment text
        Unknown:	the tag contents
        Text:		the text std::string
        @endverbatim
    */
    void SetValue(const char *_value) { value = _value; }

    /// STL std::string form.
    void SetValue(const std::string &_value) {
        StringToBuffer buf(_value);
        SetValue(buf.buffer ? buf.buffer : "");
    }

    /// Delete all the children of this node. Does not affect 'this'.
    void Clear();

    /// One step up the DOM.
    TiXmlNode *Parent() const { return parent; }

    TiXmlNode *
    FirstChild() const { return firstChild; }        ///< The first child of this node. Will be null if there are no children.
    TiXmlNode *FirstChild(
            const char *value) const;            ///< The first child of this node with the matching 'value'. Will be null if none found.

    TiXmlNode *
    LastChild() const { return lastChild; }        /// The last child of this node. Will be null if there are no children.
    TiXmlNode *LastChild(
            const char *value) const;            /// The last child of this node matching 'value'. Will be null if there are no children.

    TiXmlNode *FirstChild(const std::string &_value) const {
        return FirstChild(_value.c_str());
    }    ///< STL std::string form.
    TiXmlNode *LastChild(const std::string &_value) const {
        return LastChild(_value.c_str());
    }    ///< STL std::string form.

    /** An alternate way to walk the children of a node.
        One way to iterate over nodes is:
        @verbatim
            for( child = parent->FirstChild(); child; child = child->NextSibling() )
        @endverbatim

        IterateChildren does the same thing with the syntax:
        @verbatim
            child = 0;
            while( child = parent->IterateChildren( child ) )
        @endverbatim

        IterateChildren takes the previous child as input and finds
        the next one. If the previous child is null, it returns the
        first. IterateChildren will return null when done.
    */
    TiXmlNode *IterateChildren(TiXmlNode *previous) const;

    /// This flavor of IterateChildren searches for children with a particular 'value'
    TiXmlNode *IterateChildren(const char *value, TiXmlNode *previous) const;

    TiXmlNode *IterateChildren(const std::string &_value, TiXmlNode *previous) const {
        return IterateChildren(_value.c_str(), previous);
    }    ///< STL std::string form.

    /** Add a new node related to this. Adds a child past the LastChild.
        Returns a pointer to the new object or NULL if an error occured.
    */
    TiXmlNode *InsertEndChild(const TiXmlNode &addThis);


    /** Add a new node related to this. Adds a child past the LastChild.

        NOTE: the node to be added is passed by pointer, and will be
        henceforth owned (and deleted) by tinyXml. This method is efficient
        and avoids an extra copy, but should be used with care as it
        uses a different memory model than the other insert functions.

        @sa InsertEndChild
    */
    TiXmlNode *LinkEndChild(TiXmlNode *addThis);

    /** Add a new node related to this. Adds a child before the specified child.
        Returns a pointer to the new object or NULL if an error occured.
    */
    TiXmlNode *InsertBeforeChild(TiXmlNode *beforeThis, const TiXmlNode &addThis);

    /** Add a new node related to this. Adds a child after the specified child.
        Returns a pointer to the new object or NULL if an error occured.
    */
    TiXmlNode *InsertAfterChild(TiXmlNode *afterThis, const TiXmlNode &addThis);

    /** Replace a child of this node.
        Returns a pointer to the new object or NULL if an error occured.
    */
    TiXmlNode *ReplaceChild(TiXmlNode *replaceThis, const TiXmlNode &withThis);

    /// Delete a child of this node.
    bool RemoveChild(TiXmlNode *removeThis);

    /// Navigate to a sibling node.
    TiXmlNode *PreviousSibling() const { return prev; }

    /// Navigate to a sibling node.
    TiXmlNode *PreviousSibling(const char *) const;

    TiXmlNode *PreviousSibling(const std::string &_value) const {
        return PreviousSibling(_value.c_str());
    }    ///< STL std::string form.
    TiXmlNode *NextSibling(const std::string &_value) const {
        return NextSibling(_value.c_str());
    }    ///< STL std::string form.

    /// Navigate to a sibling node.
    TiXmlNode *NextSibling() const { return next; }

    /// Navigate to a sibling node with the given 'value'.
    TiXmlNode *NextSibling(const char *) const;

    /** Convenience function to get through elements.
        Calls NextSibling and ToElement. Will skip all non-Element
        nodes. Returns 0 if there is not another element.
    */
    TiXmlElement *NextSiblingElement() const;

    /** Convenience function to get through elements.
        Calls NextSibling and ToElement. Will skip all non-Element
        nodes. Returns 0 if there is not another element.
    */
    TiXmlElement *NextSiblingElement(const char *) const;

    TiXmlElement *NextSiblingElement(const std::string &_value) const {
        return NextSiblingElement(_value.c_str());
    }    ///< STL std::string form.

    /// Convenience function to get through elements.
    TiXmlElement *FirstChildElement() const;

    /// Convenience function to get through elements.
    TiXmlElement *FirstChildElement(const char *value) const;

    TiXmlElement *FirstChildElement(const std::string &_value) const {
        return FirstChildElement(_value.c_str());
    }    ///< STL std::string form.

    /** Query the type (as an enumerated value, above) of this node.
        The possible types are: DOCUMENT, ELEMENT, COMMENT,
                                UNKNOWN, TEXT, and DECLARATION.
    */
    virtual int Type() const { return type; }

    /** Return a pointer to the Document this node lives in.
        Returns null if not in a document.
    */
    TiXmlDocument *GetDocument() const;

    /// Returns true if this node has no children.
    bool NoChildren() const { return !firstChild; }

    TiXmlDocument *ToDocument() const {
        return (this && type == DOCUMENT) ? (TiXmlDocument *) this : 0;
    } ///< Cast to a more defined type. Will return null not of the requested type.
    TiXmlElement *ToElement() const {
        return (this && type == ELEMENT) ? (TiXmlElement *) this : 0;
    } ///< Cast to a more defined type. Will return null not of the requested type.
    TiXmlComment *ToComment() const {
        return (this && type == COMMENT) ? (TiXmlComment *) this : 0;
    } ///< Cast to a more defined type. Will return null not of the requested type.
    TiXmlUnknown *ToUnknown() const {
        return (this && type == UNKNOWN) ? (TiXmlUnknown *) this : 0;
    } ///< Cast to a more defined type. Will return null not of the requested type.
    TiXmlText *ToText() const {
        return (this && type == TEXT) ? (TiXmlText *) this : 0;
    } ///< Cast to a more defined type. Will return null not of the requested type.
    TiXmlDeclaration *ToDeclaration() const {
        return (this && type == DECLARATION) ? (TiXmlDeclaration *) this : 0;
    } ///< Cast to a more defined type. Will return null not of the requested type.

    /** Create an exact duplicate of this node and return it. The memory must be deleted
        by the caller.
    */
    virtual TiXmlNode *Clone() const = 0;

protected:
    TiXmlNode(NodeType _type);

    // Copy to the allocated object. Shared functionality between Clone, Copy constructor,
    // and the assignment operator.
    void CopyTo(TiXmlNode *target) const;

    // The real work of the input operator.
    virtual void StreamIn(TIXML_ISTREAM *in, TIXML_STRING *tag) = 0;

    // Figure out what is at *p, and parse it. Returns null if it is not an xml node.
    TiXmlNode *Identify(const char *start, TiXmlEncoding encoding);

    // Internal Value function returning a TIXML_STRING
    const TIXML_STRING &SValue() const { return value; }

    TiXmlNode *parent;
    NodeType type;

    TiXmlNode *firstChild;
    TiXmlNode *lastChild;

    TIXML_STRING value;

    TiXmlNode *prev;
    TiXmlNode *next;

private:
    TiXmlNode(const TiXmlNode &);                // not implemented.
    void operator=(const TiXmlNode &base);    // not allowed.
};


/** An attribute is a name-value pair. Elements have an arbitrary
	number of attributes, each with a unique name.

	@note The attributes are not TiXmlNodes, since they are not
		  part of the tinyXML document object model. There are other
		  suggested ways to look at this problem.
*/
class TiXmlAttribute : public TiXmlBase {
    friend class TiXmlAttributeSet;

public:
    /// Construct an empty attribute.
    TiXmlAttribute() : TiXmlBase() {
        document = 0;
        prev = next = 0;
    }

    /// std::string constructor.
    TiXmlAttribute(const std::string &_name, const std::string &_value) {
        name = _name;
        value = _value;
        document = 0;
        prev = next = 0;
    }

    /// Construct an attribute with a name and value.
    TiXmlAttribute(const char *_name, const char *_value) {
        name = _name;
        value = _value;
        document = 0;
        prev = next = 0;
    }

    const char *Name() const { return name.c_str(); }        ///< Return the name of this attribute.
    const char *Value() const { return value.c_str(); }        ///< Return the value of this attribute.
    const int
    IntValue() const;                                    ///< Return the value of this attribute, converted to an integer.
    const double
    DoubleValue() const;                                ///< Return the value of this attribute, converted to a double.

    /** QueryIntValue examines the value std::string. It is an alternative to the
        IntValue() method with richer error checking.
        If the value is an integer, it is stored in 'value' and
        the call returns TIXML_SUCCESS. If it is not
        an integer, it returns TIXML_WRONG_TYPE.

        A specialized but useful call. Note that for success it returns 0,
        which is the opposite of almost all other TinyXml calls.
    */
    int QueryIntValue(int *value) const;

    /// QueryDoubleValue examines the value std::string. See QueryIntValue().
    int QueryDoubleValue(double *value) const;

    void SetName(const char *_name) { name = _name; }                ///< Set the name of this attribute.
    void SetValue(const char *_value) { value = _value; }                ///< Set the value.

    void SetIntValue(int value);                                        ///< Set the value from an integer.
    void SetDoubleValue(double value);                                ///< Set the value from a double.

    /// STL std::string form.
    void SetName(const std::string &_name) {
        StringToBuffer buf(_name);
        SetName(buf.buffer ? buf.buffer : "error");
    }

    /// STL std::string form.
    void SetValue(const std::string &_value) {
        StringToBuffer buf(_value);
        SetValue(buf.buffer ? buf.buffer : "error");
    }

    /// Get the next sibling attribute in the DOM. Returns null at end.
    TiXmlAttribute *Next() const;

    /// Get the previous sibling attribute in the DOM. Returns null at beginning.
    TiXmlAttribute *Previous() const;

    bool operator==(const TiXmlAttribute &rhs) const { return rhs.name == name; }

    bool operator<(const TiXmlAttribute &rhs) const { return name < rhs.name; }

    bool operator>(const TiXmlAttribute &rhs) const { return name > rhs.name; }

    /*	Attribute parsing starts: first letter of the name
                         returns: the next char after the value end quote
    */
    virtual const char *Parse(const char *p, TiXmlParsingData *data, TiXmlEncoding encoding);

    virtual void StreamOut(TIXML_OSTREAM *out) const;

    // [internal use]
    // Set the document pointer so the attribute can report errors.
    void SetDocument(TiXmlDocument *doc) { document = doc; }

private:
    TiXmlAttribute(const TiXmlAttribute &);                // not implemented.
    void operator=(const TiXmlAttribute &base);    // not allowed.

    TiXmlDocument *document;    // A pointer back to a document, for error reporting.
    TIXML_STRING name;
    TIXML_STRING value;
    TiXmlAttribute *prev;
    TiXmlAttribute *next;
};


/*	A class used to manage a group of attributes.
	It is only used internally, both by the ELEMENT and the DECLARATION.
	
	The std::set can be changed transparent to the Element and Declaration
	classes that use it, but NOT transparent to the Attribute
	which has to implement a next() and previous() method. Which makes
	it a bit problematic and prevents the use of STL.

	This version is implemented with circular lists because:
		- I like circular lists
		- it demonstrates some independence from the (typical) doubly linked list.
*/
class TiXmlAttributeSet {
public:
    TiXmlAttributeSet();

    ~TiXmlAttributeSet();

    void Add(TiXmlAttribute *attribute);

    void Remove(TiXmlAttribute *attribute);

    TiXmlAttribute *First() const { return (sentinel.next == &sentinel) ? 0 : sentinel.next; }

    TiXmlAttribute *Last() const { return (sentinel.prev == &sentinel) ? 0 : sentinel.prev; }

    TiXmlAttribute *Find(const char *name) const;

private:
    TiXmlAttribute sentinel;
};


/** The element is a container class. It has a value, the element name,
	and can contain other elements, text, comments, and unknowns.
	Elements also contain an arbitrary number of attributes.
*/
class TiXmlElement : public TiXmlNode {
public:
    /// Construct an element.
    TiXmlElement(const char *in_value);

    TiXmlElement(const std::string &_value);

    TiXmlElement(const TiXmlElement &);

    void operator=(const TiXmlElement &base);

    virtual ~TiXmlElement();

    /** Given an attribute name, Attribute() returns the value
        for the attribute of that name, or null if none exists.
    */
    const char *Attribute(const char *name) const;

    /** Given an attribute name, Attribute() returns the value
        for the attribute of that name, or null if none exists.
        If the attribute exists and can be converted to an integer,
        the integer value will be put in the return 'i', if 'i'
        is non-null.
    */
    const char *Attribute(const char *name, int *i) const;

    /** Given an attribute name, Attribute() returns the value
        for the attribute of that name, or null if none exists.
        If the attribute exists and can be converted to an double,
        the double value will be put in the return 'd', if 'd'
        is non-null.
    */
    const char *Attribute(const char *name, double *d) const;

    /** QueryIntAttribute examines the attribute - it is an alternative to the
        Attribute() method with richer error checking.
        If the attribute is an integer, it is stored in 'value' and
        the call returns TIXML_SUCCESS. If it is not
        an integer, it returns TIXML_WRONG_TYPE. If the attribute
        does not exist, then TIXML_NO_ATTRIBUTE is returned.
    */
    int QueryIntAttribute(const char *name, int *value) const;

    /// QueryDoubleAttribute examines the attribute - see QueryIntAttribute().
    int QueryDoubleAttribute(const char *name, double *value) const;

    /** Sets an attribute of name to a given value. The attribute
        will be created if it does not exist, or changed if it does.
    */
    void SetAttribute(const char *name, const char *value);

    const char *Attribute(const std::string &name) const { return Attribute(name.c_str()); }

    const char *Attribute(const std::string &name, int *i) const { return Attribute(name.c_str(), i); }

    const char *Attribute(const std::string &name, double *d) const { return Attribute(name.c_str(), d); }

    int QueryIntAttribute(const std::string &name, int *value) const { return QueryIntAttribute(name.c_str(), value); }

    int QueryDoubleAttribute(const std::string &name, double *value) const {
        return QueryDoubleAttribute(name.c_str(), value);
    }

    /// STL std::string form.
    void SetAttribute(const std::string &name, const std::string &_value) {
        StringToBuffer n(name);
        StringToBuffer v(_value);
        if (n.buffer && v.buffer)
            SetAttribute(n.buffer, v.buffer);
    }

    ///< STL std::string form.
    void SetAttribute(const std::string &name, int _value) {
        StringToBuffer n(name);
        if (n.buffer)
            SetAttribute(n.buffer, _value);
    }

    /** Sets an attribute of name to a given value. The attribute
        will be created if it does not exist, or changed if it does.
    */
    void SetAttribute(const char *name, int value);

    /** Sets an attribute of name to a given value. The attribute
        will be created if it does not exist, or changed if it does.
    */
    void SetDoubleAttribute(const char *name, double value);

    /** Deletes an attribute with the given name.
    */
    void RemoveAttribute(const char *name);

    void RemoveAttribute(const std::string &name) { RemoveAttribute(name.c_str()); }    ///< STL std::string form.

    TiXmlAttribute *
    FirstAttribute() const { return attributeSet.First(); }        ///< Access the first attribute in this element.
    TiXmlAttribute *
    LastAttribute() const { return attributeSet.Last(); }        ///< Access the last attribute in this element.

    /// Creates a new Element and returns it - the returned element is a copy.
    virtual TiXmlNode *Clone() const;

    /*	Attribtue parsing starts: next char past '<'
                         returns: next char past '>'
    */
    virtual const char *Parse(const char *p, TiXmlParsingData *data, TiXmlEncoding encoding);

protected:

    void CopyTo(TiXmlElement *target) const;

    void ClearThis();    // like clear, but initializes 'this' object as well

    // Used to be public [internal use]
    virtual void StreamIn(TIXML_ISTREAM *in, TIXML_STRING *tag);

    virtual void StreamOut(TIXML_OSTREAM *out) const;

    /*	[internal use]
        Reads the "value" of the element -- another element, or text.
        This should terminate with the current end tag.
    */
    const char *ReadValue(const char *in, TiXmlParsingData *prevData, TiXmlEncoding encoding);

private:

    TiXmlAttributeSet attributeSet;
};


/**	An XML comment.
*/
class TiXmlComment : public TiXmlNode {
public:
    /// Constructs an empty comment.
    TiXmlComment() : TiXmlNode(TiXmlNode::COMMENT) {}

    TiXmlComment(const TiXmlComment &);

    void operator=(const TiXmlComment &base);

    virtual ~TiXmlComment() {}

    /// Returns a copy of this Comment.
    virtual TiXmlNode *Clone() const;

    /*	Attribtue parsing starts: at the ! of the !--
                         returns: next char past '>'
    */
    virtual const char *Parse(const char *p, TiXmlParsingData *data, TiXmlEncoding encoding);

protected:
    void CopyTo(TiXmlComment *target) const;

    // used to be public
    virtual void StreamIn(TIXML_ISTREAM *in, TIXML_STRING *tag);

    virtual void StreamOut(TIXML_OSTREAM *out) const;

private:

};


/** XML text. Contained in an element.
*/
class TiXmlText : public TiXmlNode {
    friend class TiXmlElement;

public:
    /// Constructor.
    TiXmlText(const char *initValue) : TiXmlNode(TiXmlNode::TEXT) {
        SetValue(initValue);
    }

    virtual ~TiXmlText() {}

    /// Constructor.
    TiXmlText(const std::string &initValue) : TiXmlNode(TiXmlNode::TEXT) {
        SetValue(initValue);
    }

    TiXmlText(const TiXmlText &copy) : TiXmlNode(TiXmlNode::TEXT) { copy.CopyTo(this); }

    void operator=(const TiXmlText &base) { base.CopyTo(this); }

    virtual const char *Parse(const char *p, TiXmlParsingData *data, TiXmlEncoding encoding);

protected :
    ///  [internal use] Creates a new Element and returns it.
    virtual TiXmlNode *Clone() const;

    void CopyTo(TiXmlText *target) const;

    virtual void StreamOut(TIXML_OSTREAM *out) const;

    bool Blank() const;    // returns true if all white space and new lines
    // [internal use]
    virtual void StreamIn(TIXML_ISTREAM *in, TIXML_STRING *tag);

private:
};


/** In correct XML the declaration is the first entry in the file.
	@verbatim
		<?xml version="1.0" standalone="yes"?>
	@endverbatim

	TinyXml will happily read or write files without a declaration,
	however. There are 3 possible attributes to the declaration:
	version, encoding, and standalone.

	Note: In this version of the code, the attributes are
	handled as special cases, not generic attributes, simply
	because there can only be at most 3 and they are always the same.
*/
class TiXmlDeclaration : public TiXmlNode {
public:
    /// Construct an empty declaration.
    TiXmlDeclaration() : TiXmlNode(TiXmlNode::DECLARATION) {}

    /// Constructor.
    TiXmlDeclaration(const std::string &_version,
                     const std::string &_encoding,
                     const std::string &_standalone);

    /// Construct.
    TiXmlDeclaration(const char *_version,
                     const char *_encoding,
                     const char *_standalone);

    TiXmlDeclaration(const TiXmlDeclaration &copy);

    void operator=(const TiXmlDeclaration &copy);

    virtual ~TiXmlDeclaration() {}

    /// Version. Will return an empty std::string if none was found.
    const char *Version() const { return version.c_str(); }

    /// Encoding. Will return an empty std::string if none was found.
    const char *Encoding() const { return encoding.c_str(); }

    /// Is this a standalone document?
    const char *Standalone() const { return standalone.c_str(); }

    /// Creates a copy of this Declaration and returns it.
    virtual TiXmlNode *Clone() const;

    virtual const char *Parse(const char *p, TiXmlParsingData *data, TiXmlEncoding encoding);

protected:
    void CopyTo(TiXmlDeclaration *target) const;

    // used to be public
    virtual void StreamIn(TIXML_ISTREAM *in, TIXML_STRING *tag);

    virtual void StreamOut(TIXML_OSTREAM *out) const;

private:

    TIXML_STRING version;
    TIXML_STRING encoding;
    TIXML_STRING standalone;
};


/** Any tag that tinyXml doesn't recognize is saved as an
	unknown. It is a tag of text, but should not be modified.
	It will be written back to the XML, unchanged, when the file
	is saved.

	DTD tags get thrown into TiXmlUnknowns.
*/
class TiXmlUnknown : public TiXmlNode {
public:
    TiXmlUnknown() : TiXmlNode(TiXmlNode::UNKNOWN) {}

    virtual ~TiXmlUnknown() {}

    TiXmlUnknown(const TiXmlUnknown &copy) : TiXmlNode(TiXmlNode::UNKNOWN) { copy.CopyTo(this); }

    void operator=(const TiXmlUnknown &copy) { copy.CopyTo(this); }

    /// Creates a copy of this Unknown and returns it.
    virtual TiXmlNode *Clone() const;

    virtual const char *Parse(const char *p, TiXmlParsingData *data, TiXmlEncoding encoding);

protected:
    void CopyTo(TiXmlUnknown *target) const;

    virtual void StreamIn(TIXML_ISTREAM *in, TIXML_STRING *tag);

    virtual void StreamOut(TIXML_OSTREAM *out) const;

private:

};


/** Always the top level node. A document binds together all the
	XML pieces. It can be saved, loaded, and printed to the screen.
	The 'value' of a document node is the xml file name.
*/
class TiXmlDocument : public TiXmlNode {
public:
    /// Create an empty document, that has no name.
    TiXmlDocument();

    /// Create a document with a name. The name of the document is also the filename of the xml.
    TiXmlDocument(const char *documentName);

    /// Constructor.
    TiXmlDocument(const std::string &documentName);

    TiXmlDocument(const TiXmlDocument &copy);

    void operator=(const TiXmlDocument &copy);

    virtual ~TiXmlDocument() {}

    /** Load a file using the current document value.
        Returns true if successful. Will delete any existing
        document data before loading.
    */
    bool LoadFile(TiXmlEncoding encoding = TIXML_DEFAULT_ENCODING);

    /// Load a file using the given filename. Returns true if successful.
    bool LoadFile(const char *filename, TiXmlEncoding encoding = TIXML_DEFAULT_ENCODING);

    bool LoadFile(const std::string &filename,
                  TiXmlEncoding encoding = TIXML_DEFAULT_ENCODING)            ///< STL std::string version.
    {
        StringToBuffer f(filename);
        return (f.buffer && LoadFile(f.buffer, encoding));
    }

    bool SaveFile(const std::string &filename) const        ///< STL std::string version.
    {
        StringToBuffer f(filename);
        return (f.buffer && SaveFile(f.buffer));
    }

    /** Parse the given null terminated block of xml data. Passing in an encoding to this
        method (either TIXML_ENCODING_LEGACY or TIXML_ENCODING_UTF8 will force TinyXml
        to use that encoding, regardless of what TinyXml might otherwise try to detect.
    */
    virtual const char *
    Parse(const char *p, TiXmlParsingData *data = 0, TiXmlEncoding encoding = TIXML_DEFAULT_ENCODING);

    /** Get the root element -- the only top level element -- of the document.
        In well formed XML, there should only be one. TinyXml is tolerant of
        multiple elements at the document level.
    */
    TiXmlElement *RootElement() const { return FirstChildElement(); }

    /** If an error occurs, Error will be std::set to true. Also,
        - The ErrorId() will contain the integer identifier of the error (not generally useful)
        - The ErrorDesc() method will return the name of the error. (very useful)
        - The ErrorRow() and ErrorCol() will return the location of the error (if known)
    */
    bool Error() const { return error; }

    /// Contains a textual (english) description of the error if one occurs.
    const char *ErrorDesc() const { return errorDesc.c_str(); }

    /** Generally, you probably want the error std::string ( ErrorDesc() ). But if you
        prefer the ErrorId, this function will fetch it.
    */
    const int ErrorId() const { return errorId; }

    /** Returns the location (if known) of the error. The first column is column 1,
        and the first row is row 1. A value of 0 means the row and column wasn't applicable
        (memory errors, for example, have no row/column) or the parser lost the error. (An
        error in the error reporting, in that case.)

        @sa SetTabSize, Row, Column
    */
    int ErrorRow() { return errorLocation.row + 1; }

    int ErrorCol() { return errorLocation.col + 1; }    ///< The column where the error occured. See ErrorRow()

    /** By calling this method, with a tab size
        greater than 0, the row and column of each node and attribute is stored
        when the file is loaded. Very useful for tracking the DOM back in to
        the source file.

        The tab size is required for calculating the location of nodes. If not
        std::set, the default of 4 is used. The tabsize is std::set per document. Setting
        the tabsize to 0 disables row/column tracking.

        Note that row and column tracking is not supported when using operator>>.

        The tab size needs to be enabled before the parse or load. Correct usage:
        @verbatim
        TiXmlDocument doc;
        doc.SetTabSize( 8 );
        doc.Load( "myfile.xml" );
        @endverbatim

        @sa Row, Column
    */
    void SetTabSize(int _tabsize) { tabsize = _tabsize; }

    int TabSize() const { return tabsize; }

    /** If you have handled the error, it can be reset with this call. The error
        state is automatically cleared if you Parse a new XML block.
    */
    void ClearError() {
        error = false;
        errorId = 0;
        errorDesc = "";
        errorLocation.row = errorLocation.col = 0;
        //errorLocation.last = 0;
    }


    virtual void StreamOut(TIXML_OSTREAM *out) const;

    // [internal use]
    void SetError(int err, const char *errorLocation, TiXmlParsingData *prevData, TiXmlEncoding encoding);

protected :
    // [internal use]
    virtual TiXmlNode *Clone() const;

    virtual void StreamIn(TIXML_ISTREAM *in, TIXML_STRING *tag);

private:
    void CopyTo(TiXmlDocument *target) const;

    bool error;
    int errorId;
    TIXML_STRING errorDesc;
    int tabsize;
    TiXmlCursor errorLocation;
};


/**
	A TiXmlHandle is a class that wraps a node pointer with null checks; this is
	an incredibly useful thing. Note that TiXmlHandle is not part of the TinyXml
	DOM structure. It is a separate utility class.

	Take an example:
	@verbatim
	<Document>
		<Element attributeA = "valueA">
			<Child attributeB = "value1" />
			<Child attributeB = "value2" />
		</Element>
	<Document>
	@endverbatim

	Assuming you want the value of "attributeB" in the 2nd "Child" element, it's very 
	easy to write a *lot* of code that looks like:

	@verbatim
	TiXmlElement* root = document.FirstChildElement( "Document" );
	if ( root )
	{
		TiXmlElement* element = root->FirstChildElement( "Element" );
		if ( element )
		{
			TiXmlElement* child = element->FirstChildElement( "Child" );
			if ( child )
			{
				TiXmlElement* child2 = child->NextSiblingElement( "Child" );
				if ( child2 )
				{
					// Finally do something useful.
	@endverbatim

	And that doesn't even cover "else" cases. TiXmlHandle addresses the verbosity
	of such code. A TiXmlHandle checks for null	pointers so it is perfectly safe 
	and correct to use:

	@verbatim
	TiXmlHandle docHandle( &document );
	TiXmlElement* child2 = docHandle.FirstChild( "Document" ).FirstChild( "Element" ).Child( "Child", 1 ).Element();
	if ( child2 )
	{
		// do something useful
	@endverbatim

	Which is MUCH more concise and useful.

	It is also safe to copy handles - internally they are nothing more than node pointers.
	@verbatim
	TiXmlHandle handleCopy = handle;
	@endverbatim

	What they should not be used for is iteration:

	@verbatim
	int i=0; 
	while ( true )
	{
		TiXmlElement* child = docHandle.FirstChild( "Document" ).FirstChild( "Element" ).Child( "Child", i ).Element();
		if ( !child )
			break;
		// do something
		++i;
	}
	@endverbatim

	It seems reasonable, but it is in fact two embedded while loops. The Child method is 
	a linear walk to find the element, so this code would iterate much more than it needs 
	to. Instead, prefer:

	@verbatim
	TiXmlElement* child = docHandle.FirstChild( "Document" ).FirstChild( "Element" ).FirstChild( "Child" ).Element();

	for( child; child; child=child->NextSiblingElement() )
	{
		// do something
	}
	@endverbatim
*/
class TiXmlHandle {
public:
    /// Create a handle from any node (at any depth of the tree.) This can be a null pointer.
    TiXmlHandle(TiXmlNode *node) { this->node = node; }

    /// Copy constructor
    TiXmlHandle(const TiXmlHandle &ref) { this->node = ref.node; }

    TiXmlHandle operator=(const TiXmlHandle &ref) {
        this->node = ref.node;
        return *this;
    }

    /// Return a handle to the first child node.
    TiXmlHandle FirstChild() const;

    /// Return a handle to the first child node with the given name.
    TiXmlHandle FirstChild(const char *value) const;

    /// Return a handle to the first child element.
    TiXmlHandle FirstChildElement() const;

    /// Return a handle to the first child element with the given name.
    TiXmlHandle FirstChildElement(const char *value) const;

    /** Return a handle to the "index" child with the given name.
        The first child is 0, the second 1, etc.
    */
    TiXmlHandle Child(const char *value, int index) const;

    /** Return a handle to the "index" child.
        The first child is 0, the second 1, etc.
    */
    TiXmlHandle Child(int index) const;

    /** Return a handle to the "index" child element with the given name.
        The first child element is 0, the second 1, etc. Note that only TiXmlElements
        are indexed: other types are not counted.
    */
    TiXmlHandle ChildElement(const char *value, int index) const;

    /** Return a handle to the "index" child element.
        The first child element is 0, the second 1, etc. Note that only TiXmlElements
        are indexed: other types are not counted.
    */
    TiXmlHandle ChildElement(int index) const;

    TiXmlHandle FirstChild(const std::string &_value) const { return FirstChild(_value.c_str()); }

    TiXmlHandle FirstChildElement(const std::string &_value) const { return FirstChildElement(_value.c_str()); }

    TiXmlHandle Child(const std::string &_value, int index) const { return Child(_value.c_str(), index); }

    TiXmlHandle ChildElement(const std::string &_value, int index) const { return ChildElement(_value.c_str(), index); }

    /// Return the handle as a TiXmlNode. This may return null.
    TiXmlNode *Node() const { return node; }

    /// Return the handle as a TiXmlElement. This may return null.
    TiXmlElement *Element() const { return ((node && node->ToElement()) ? node->ToElement() : 0); }

    /// Return the handle as a TiXmlText. This may return null.
    TiXmlText *Text() const { return ((node && node->ToText()) ? node->ToText() : 0); }

    /// Return the handle as a TiXmlUnknown. This may return null;
    TiXmlUnknown *Unknown() const { return ((node && node->ToUnknown()) ? node->ToUnknown() : 0); }

private:
    TiXmlNode *node;
};
